TR Dizin İndeksli Yayınlar Koleksiyonu / TR Dizin Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14365/4
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Article Citation - WoS: 2Citation - Scopus: 2Neural Correlates of Opponent Processes for Financial Gains and Losses(Ege Univ, 2019-06-24) Erdeniz, Burak; Done, JohnObjective: Functional imaging studies offer alternative explanations for the neural correlates of monetary gain and loss related brain activity, and their opponents, omission of gains and losses. One possible explanation based on the psychology of opponent process theory suggests that successful avoidance of an aversive outcome is itself rewarding, and hence activates brain regions involved in reward processing. In order to test this hypothesis, we compared brain activation for successful avoidance of losses and receipt of monetary gains. Additionally, the brain regions involved in processing of frustrative neutral outcomes and actual losses were compared in order to test whether these two representations are coded in common or distinct brain regions. Methods: Using a 3 Tesla functional magnetic resonance imaging machine, fifteen healthy volunteers between the ages 22 to 28 were scanned for blood oxygen level dependent signal changes while they were performing a probabilistic learning task, wherein each trial a participant chose one of the two available options in order to win or avoid losing money. Results: The results confirmed, previous findings showing that medial frontal cortex and ventral striatum show significant activation (p<0.001) not only for monetary gains but also for successful avoidance of losses. A similar activation pattern was also observed for monetary losses and avoidance of gains in the medial frontal cortex, and posterior cingulate cortex, however, there was increased activation in a mygdala specific to monetary losses (p<0.001). Further, subtraction analysis showed that regardless of the type of loss (i.e., frustrative neutral outcomes) posterior insula showed increased activation. Conclusion: This study provides evidence for a significant overlap not only between gains and losses, but also between their opponents. The results suggested that the overlapping activity pattern in the medial frontal cortex could be explained by a more abstract function of medial frontal cortex, such as outcome evaluation or performance monitoring, which possibly does not differentiate between winning and losing monetary outcomes.Article Citation - WoS: 2Citation - Scopus: 1Towards Automaticity in Reinforcement Learning: a Model-Based Functional Magnetic Resonance Imaging Study(Turkish Neuropsychiatry Assoc-Turk Noropsikiyatri Dernegi, 2019) Erdeniz, Burak; Done, JohnIntroduction: Previous studies showed that over the course of learning many neurons in the medial prefrontal cortex adapt their firing rate towards the options with highest predicted value reward but it was showed that during later learning trials the brain switches to a more automatic processing mode governed by the basal ganglia. Based on this evidence, we hypothesized that during the early learning trials the predicted values of chosen options will be coded by a goal directed system in the medial frontal cortex but during the late trials the predicted values will be coded by the habitual learning system in the dorsal striatum. Methods: In this study, using a 3 Tesla functional magnetic resonance imaging scanner (fMRI), blood oxygen level dependent signal (BOLD) data was collected whilst participants (N=12) performed a reinforcement learning task. The task consisted of instrumental conditioning trials wherein each trial a participant choose one of the two available options in order to win or avoid losing money. In addition to that, depending on the experimental condition, participants received either monetary reward (gain money), monetary penalty (lose money) or neural outcome. Results: Using model-based analysis for functional magnetic resonance imaging (fMRI) event related designs; region of interest (ROI) analysis was performed to nucleus accumbens, medial frontal cortex, caudate nucleus, putamen and globus pallidus internal and external segments. In order to compare the difference in brain activity for early (goal directed) versus late learning (habitual, automatic) trials, separate ROI analyses were performed for each anatomical sub-region. For the reward condition, we found significant activity in the medial frontal cortex (p<0.05) only for early learning trials but activity is shifted to bilateral putamen (p<0.05) during later trials. However, for the loss condition no significant activity was found for early trials except globus pallidus internal segment showed a significant activity (p<0.05) for later trials. Conclusion: We found that during reinforcement learning activation in the brain shifted from the medial frontal regions to dorsal regions of the striatum. These findings suggest that there are two separable (early goal directed and late habitual) learning systems in the brain.Article Citation - WoS: 2Evaluation of Women's Beliefs About Pap Smear Screening Using the Health Belief Model Scale(Istanbul Univ, Fac Medicine, Publ Off, 2020-10-19) Aygun, Olgu; Gokdemir, Ozden; Bulut, Ulku; Yaprak, Seval; Ozcakar, Nilgun; Batur, Ülkü BulutObjective: To evaluate women's beliefs about screening Pap smear test. Material and Method: The survey has been conducted through a questionnaire prepared by researchers, based on the Health Belief Model Scale for the Pap smear test. The participants consisted of 266 women between 18-70 years of age registered at a Family Health Center in Izmir. Their beliefs about screening Pap smear test were evaluated using the Health Belief Model Scale. Results: The mean age of first sexual intercourse was 21.67 +/- 4.5 (min:13--max:45 years), 86.5% reported a single partner and 41.0% of them (n=109) had never undergone a Pap smear test. Women who previously had a Pap smear test had high scores of sensitivity, seriousness, advantage and motivation, health motivation subscales, but the mean scores for obstacles were low. There was a difference between seriousness, health motivation subscales and taking the Pap smear test (p=0.021, p=0.006). The Mean scores of seriousness and health motivation of Health Belief Model Scale were higher. There was no difference between education level, working status and undergoing a Pap test (p>0.05). Conclusion: Having a Pap smear test is still moderately frequent and there are obstacles. Planning the interventions to eliminate Pap smear test barriers is an important issue for family physicians.Article Citation - WoS: 2Customer Service Failure Evaluations in Diverse Airlines Business Models(Ege Univ, Fac Economics & Admin Sciences, 2019-10-26) Dobrucali, Birce; Oflac, BenguEven though it is impossible to eliminate all failures in a service encounter, due to their negative outcomes, airlines' strive at minimizing failures as much as possible. Customers may act differently after failures, but the important point for airlines is to understand the underlying psychological mechanisms for prevention. In this regard, this study reveals the dynamics by which expectancies of passengers affect stability attribution, word of mouth (WOM) and repurchase intentions after exposing service failures in diverse airlines business models. Structural equation modeling is used to compare models in two airlines business contexts: low cost carriers (LCCs) and flagship airlines. Findings demonstrate that for LCC, passengers' expectations positively affect stability attributions. Additionally, stability attribution following flagship airlines service failure is found to have a negative effect on repurchase intentions. Finally, findings indicate that following both LCC and flagship service failures, stability attribution decreases WOM intention of passengers.Article Citation - WoS: 1Children in Urban Environments: a Case Study From a Dense Neighbourhood in Izmir-Turkey(Yildiz Technical Univ, Fac Architecture, 2022) Dikmen Güleryüz, Oylum; Dogan, Fehmi; Kasali, Altug; Guleryuz, Oylum DikmenThe aim of this study is to understand children's engagement with their urban outdoor environments in Izmir-Turkey, a city with a high urbanisation rate, and to explore the factors that affect their outdoor preferences outside of their school time. The study consists of a field study conducted in a densely populated middle-income neighbourhood. Participants are fourth-grade children from a state-run primary school aged 9-11 years (n=44) and their parents (n=40). The study followed a multi-methodological approach, employing questionnaires, drawing and story writing tasks as data collection methods. Results of the study showed the strong tendency to prefer outdoors during their free time even when their neighbourhood is a high-density urban settlement with limited opportunities for outdoor activities. In the studied neighbourhood, most of the participants mentioned the schoolyard over other locations as their preferred place fin- outdoor play. Other than the schoolyard, the children mainly reported familiar places in their neighbourhoods, close to their local environments which were also depicted in their drawings and described in their stories. From the perspectives of urban designers and policy-makers, the findings of the study highlight aspects to be concerned about opportunities for outdoor play in high-density and urbanised central neighbourhoods.